EVALUATION OF NEUROPROTECTIVE ACTIVITY OF ALBIZIA JULIBRISSIN LEAF EXTRACT AGAINST SCOPOLAMINE-INDUCED ALZHEIMER'S DISEASE IN RATS

Abstract

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline, cholinergic dysfunction, oxidative stress, and neuronal degeneration, for which currently available therapies provide only symptomatic relief. The present study evaluated the neuroprotective activity of hydroalcoholic Albizia julibrissin leaf extract against scopolamine-induced Alzheimer's disease in Wistar rats. Animals were divided into five groups: normal control, scopolamine control, Donepezil (5 mg/kg), low-dose extract (200 mg/kg), and high-dose extract (400 mg/kg). Cognitive function was assessed using the Morris Water Maze, Elevated Plus Maze, and Passive Avoidance tests, while brain acetylcholinesterase (AChE) activity was estimated by Ellman's method, followed by histopathological examination of brain tissue. Scopolamine administration produced significant cognitive impairment, elevated AChE activity (0.65 ± 0.04 μmol/min/mg protein) compared with the normal control (0.30 ± 0.02 μmol/min/mg protein), and marked neuronal degeneration. Treatment with Albizia julibrissin significantly improved behavioral performance in all memory models and reduced AChE activity to 0.48 ± 0.03 and 0.38 ± 0.03 μmol/min/mg protein at 200 and 400 mg/kg, respectively. The high-dose extract markedly reduced escape latency, transfer latency, increased step-through latency, and preserved normal neuronal architecture, producing neuroprotective effects comparable to Donepezil. These findings demonstrate that Albizia julibrissin leaf extract exerts significant dose-dependent neuroprotective and cognition-enhancing effects, possibly through restoration of cholinergic neurotransmission and preservation of neuronal integrity. The study suggests that Albizia julibrissin may serve as a promising plant-derived therapeutic candidate for the management of Alzheimer's disease, although further molecular and clinical investigations are required to validate its therapeutic potential.